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Go to Brilliant.org/SciShow to learn more. [ intro ]. Food, glorious food.

We need it to live, and stuff. But for many people, it's more than that -- a hobby, a pastime, a passion. Farms and businesses work hard to satisfy the commercial and cultural needs of foodies the world over.

But not everything can be plunked down in the ground and picked a few months later, or grown happily in a tank. Some foodstuffs just aren't that cooperative. No matter how much we want them, the science of these plants, animals, and fungi is at odds with the demand.

Take huckleberries for example. They're kind of a big deal in the Pacific Northwest of the United States, as flocks of people head out into the woods every summer looking to fill their baskets with the sweet and juicy berries. They are in such demand that huckleberry picking season is now a regulated event in some areas to help make sure there's enough fruit to go around.

You see, these berries have a reputation of being difficult to grow in a farm setting. The soil conditions need to be just right. If you're trying to grow them, .

Additionally, in the wild, huckleberry grows at high elevations. This environment provides an insulating cover of snow to help protect the plant during the sub-zero temperatures of winter. Without this insulation phenomenon at lower elevations, the plants simply freeze.

And it's hard to replicate these conditions in other climates. Like, imagine carting in a bunch of fake snow, then keeping it frozen. Not to mention, they just grow painfully slow. it can take up to 15 years after planting seeds or cuttings to yield harvestable fruit.

But maybe we're approaching them all wrong. After all, indigenous peoples have been cultivating huckleberry crops for centuries -- by managing the wild plants. They were the ones who taught early European arrivals to North America how to forage for the ripe berries.

And over time this practice of foraging, cooking, and preserving evolved into the high-demand craze that we see every year. At least here in Montana! Researchers have been working on creating a domestic variant of the huckleberry by cross-breeding it with certain strains of blueberries, which are closely related to huckleberries.

These cultivars would be able to thrive in a variety of ecological settings, making it more likely that the number of crops could rise to meet the demand. But until that happens, the huckleberry will remain a treat for dedicated berry-hunters. And only at certain times of the year.

And that's not the only luxury food product in high demand. According to sushi lovers, n nothing beats the flavor of bluefin tuna. In 2019, a single large tuna in Japan sold for over three million dollars!

Since these fish are only found in the wild, high demand has led to high prices and overfishing -- landing the bluefin on the endangered species list. We can't grow these fish in hatcheries yet, because bluefin tuna have a complex life cycle, making them very difficult to farm. They are a really big fish.

Like, over three meters long and averaging two hundred fifty kilograms big. They're fast-swimming, migratory fish, meaning their natural habitat is much, much bigger than any tank. They need to swim to develop properly.

Plus, they're predators at the top of the food chain, so it also takes a lot of energy to produce the animals they like to snack on. So the mature adults are difficult to care for, to say the least. But even as tiny free-floating larvae, they are difficult to maintain.

A study published in 1991, for example, showed when larvae of one species of bluefin tuna are packed in tightly, they grow more slowly, and fewer of them survive. That study actually looked at conditions in the wild, but with an eye toward what would happen in a tank -- though measures could also be taken to avoid such issues. Also, larvae may be little, but their heads take up most of their size, so they're… a little top heavy.

So tank conditions need to be just right to prevent them from literally sinking and actually getting hurt when they hit the bottom. Because of their size, it can take up to 8 years for them to reach sexual maturity and spawn more fish. And fish in captivity often experience reproductive issues.

Researchers in the EU and the US are trying to overcome this issue by manipulating the fish's own growth hormones to induce reproduction. If we can't establish captive populations to keep up with demand, overfishing is likely to continue -- which could be bad news for this fishy favorite. Other high demand foods are at risk of becoming endangered, too.

The truffle is the poster child of expensive luxury foods. Some varieties of truffle can sell for hundreds of dollars per ounce. But this fungus could go the way of the dodo unless we figure out how to grow it ourselves.

See, truffles aren't like the mushrooms you're probably familiar with. They grow underground in close proximity to the root systems of trees, usually hardwoods. They are mycorrhizal species, which means they have a symbiotic relationship with the trees in which they exchange nutrients and aid each other's growth.

But humans haven't been doing a good job of caring for this fungus. Because deforestation and climate change are major threats to the forests across southern Europe that truffles call home in the wild. And they're costly and difficult to grow in a farm setting, mostly because it takes time to grow a fungus with such a complex life history.

One researcher in the UK harvested his first truffle almost 10 years after planting the holly oak tree that would develop a relationship with the fungi. However, there might be a small silver lining to the role that climate change has taken. Even though the native habitats of truffle fungi are being destroyed, areas in more northerly forests in Europe may be growing more amenable to these species.

Given time, the ecosystem changes from climate change might just provide the opportunity for truffles to move to brand new habitats. Our demand for these foodstuffs outstrips the supply. It seems unlikely that sushi fans or huckleberry lovers will let them go any time soon, so we may need to apply some clever science in order to cultivate them.

In addition to farming, though, this may be the incentive we need to preserve native habitats for the survival of all species -- including the delicious ones. Because after all, isn't biodiversity the spice of life?

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